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ICES O

CEANOGRAPHY

C

OMMITTEE

ICES CM 2006/OCC:04 Ref. ACME

R EPORT OF THE

ICES-IOC W ^ORKING G ^{ROUP ON} H ARMFUL A LGAL B LOOM D YNAMICS

(WGHABD)

3-6 A PRIL 2006

G DYNIA , P OLAND

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DK-1553 Copenhagen V Denmark

Telephone (+45) 33 38 67 00 Telefax (+45) 33 93 42 15 www.ices.dk

[email protected]

Recommended format for purposes of citation:

ICES. 2006. Report of the ICES-IOC Working Group on Harmful Algal Bloom Dynamics (WGHABD), 3-6 April 2006, Gdynia, Poland. ICES CM 2006/OCC:04. 47 pp.

For permission to reproduce material from this publication, please apply to the General Secretary.

The document is a report of an Expert Group under the auspices of the International Council for the Exploration of the Sea and does not necessarily represent the views of the Council.

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Executive Summary

The ICES-IOC Working Group of Harmful Algal Bloom Dynamics meeting was hosted by the Institute of Oceanography of the University of Gdansk, in Gdynia, Poland from 3–6 April 2006. 26 scientists from thirteen countries participated. This was a very successful meeting with a challenging set of terms of reference to deal with in the time available.

Nevertheless, the group made 35 presentations under the terms of reference and this report is a summary of these presentations and discussions.

Over the three and a half days, the group dealt with:

• Progress in the detection of harmful algal blooms and their dynamics by remote sensing techniques.

• Reviewed the section on Phytoplankton Monitoring in the Report of the Joint FAO/IOC/WHO Ad Hoc Expert Consultation.

• Reviewed the outcome of the Workshop on New and Classical Techniques in Enumeration of Phytoplankton.

• Reviewed the progress and analyses that REGNS North Sea Group has made.

• Discuss new findings that pertain to harmful algal bloom dynamics.

• Reviewed the on-line format of HAEDAT submission form.

• Reviewed the structure and composition of the decadal HAE maps.

• Collated and assessed National reports.

• Discussed potential contributions to the ecosystem overview.

These are dealt with in detail in the report (Sections 5 to 15).

New Findings

Eight presentations were made by the group to report new findings in the area of HAB dynamics. These included the summary of a three year project on HAB oceanography in Ireland (BOHAB), The use of Flowcam™ in phytoplankton enumeration, A summary of Spirolides and Microcystin chemistry, The detection of Azaspiracid in crabs, a summary of the seasonality of Dinophysis in the Swedish Skagerak. Additionally, there were three notable, unusual blooms brought to the groups attention: Alexandrium fundyense in the Gulf of Maine, Alexandrium in the Bay of Fundy, and an exceptional bloom of Karenia mikimotoi in Ireland.

More details of these presentations are given in the New Findings section of this report (Section 10)

The group also had the opportunity to have a half day joint session with the WGGIB (Working Group on GEOHAB implementation in the Baltic). Presentations by this group included reports on New Nodularin analogs in the Baltic, Phosphorus dynamics in the Baltic during a cyanobacterial bloom, satellite methods in Baltic system monitoring, Ecosystem effects and health hazards of Cyanotoxins, Nodularin concentrations in Southern Baltic sediments, mussels and Flounder, and latest news on BMAA neurotoxin in the Baltic Sea. These are reported in detail in the WGGIB report.

National Reports

One of the most useful functions provided by WGHABD is an annual opportunity for international delegates to compare international trends in HAB events. At the 2006 workshop twelve countries presented national reports for discussion, of which there are ten reported in this document. 2005 saw several noteworthy or exceptional HAB events.

• The USA experienced one of its most intense blooms of Alexandrium fundyense, which caused PSP all along the coast of New England. A second unusual HAB

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was the bloom of Karenia brevis which lasted all through 2005 in the Florida area, killing fish, mammals and birds, and causing respiratory problems in humans.

• Farther north in Canada, it was a fairly unexceptional year with the usual round of closures experienced both on the east and west coasts from PSP.

• On the other side of the Atlantic, Norway did not record ASP toxicity even following a dense bloom of 16 million Pseudo-nitzschia cells/L recorded. Small events of DSP and PSP toxicity were recorded with levels exceeding the quarantine levels at only a few monitoring stations. AZA was detected for the first time in Crabs.

• Estonia recorded exceptionally low levels of Nodularia when compared to the annual trends,

• Poland also reported 2005 as being a “moderate” year for Nodularia.

• Denmark did not experience any PSP or DSP, however ASP was detected for the first time in mussels from Danish waters.

• The UK reported the presence of Alexandrium spp. presence in moderate levels in England at 1.8 million cells/L and low levels in Scotland > 1300cells/L. These did not coincide with PSP in shellfish. Low levels of Dinophysis were also reported. Pseudo-nitzschia were more widespread and persistent than previous years but the concentrations were not particularly high. The Karenia bloom that affected the Republic of Ireland did not extend into UK waters.

• Ireland did in contrast, however, experience a high number of HAB related problems in 2005. For the first time a major ASP event was recorded in both samples of M.edulis and C.gigas associated with a bloom of Pseudo-nitzschia.

Extensive DSP toxicity was detected through the summer months in all areas and then quarantine levels of AZA, lasted right through the following autumn and winter months. Low levels of Alexandrium were detected through the summer without any toxicity, apart from a small PSP outbreak in Cork in June. Finally a bloom of Karenia mikimotoi wreaked havoc on the benthic and pelagic communities during June and July.

• The Netherlands reported a bloom of Phaeocystis in February which is earlier than normal, resulting eventually in a 10 million cell/L bloom. In May this peaked at 138 million cells/L. Moderate levels of Dinophysis were recorded which resulted in levels slightly above quarantine level of DTX-3 as recorded by LCMS.

• In Spain, a very intense Gymnodinium catenatum bloom (after 10 years of absence!) occurred from October to December affecting all the production areas in the Rías Baixas and some areas in the Northen Galician coast. Maximum G.

catenatum concentration was 1.7·10⁵ cell·l⁻¹ and maximum level of accumulated toxins 4080 µg STXeq·100 g⁻¹ meat.

Full text of these National reports and the other Terms of Reference are given in the body of the report.

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1 Welcome and opening of the Meeting

Following a welcome by the Chair, the Deputy Director of the Institute of Oceanography, Dr Hanna Mazur-Marzec, opened the meeting on the 3 April 2005. The participants were introduced with respect to their names, institute, national affiliation and fields of expertise.

The agenda was agreed and Dr Pat Tester and Dr Eileen Bresnan elected as joint Rapporteur.

The list of participants is presented in Annex 1. The meeting agenda is presented in Annex 2.

The Chair invited comments and review from the outgoing Chair of WGHABD, Dr Jennifer Martin relating to the WGHABD report presented to ICES Oceanography Committee from the 2005 meeting. She reported to the group that the oceanography committee felt the report was well organized, informative and the meeting well attended. While primarily concerned with HABs, the WG was not just addressing the dynamics but also more general areas of HAB science. An example of this was the co-ordination of the Intercomparison Workshop on New and Classic Techniques for the Determination of Numerical Abundance and Biovolume of HAB-Species Evaluation of the Cost, Time Efficiency and Intercalibration Methods (WKNCT) held in Kristineberg, Sweden 22–27 August 2005.

Being a joint ICES-IOC working group, the IOC in most years announces the possibility for its Member Countries outside the ICES area to attend WGHABD and offers travel support. In 2006 however, the IOC were not in a position to offer this support due to other demands on their budget. The IOC did support the intercomparison workshop (WKNCT). The IOC also supports the general aims of WGHABD, and continues valuable interaction regarding data collection and management of HAB data through the development of the HAEDAT database.

The Terms of Reference for 2005 were reviewed and adopted.

2 Terms of Reference

At the 92nd Statutory Meeting (2005), Aberdeen, Scotland, the Council approved the WGHABD (2005) Terms of References:

The ICES-IOC Working Group on Harmful Algal Bloom Dynamics [WGHABD] (Chair J.Silke Ireland) will meet in Gdynia, Poland, from 3–6 April 2006 to:

a ) Review progress in the detection of harmful algal blooms and their dynamics by remote sensing techniques and examining results from new sensors and algorithms as well as validation procedures used for HAB observations.

b ) Review the section on Phytoplankton Monitoring in the Report of the Joint FAO/IOC/WHO Ad Hoc Expert Consultation for Codex Alimentarius on Biotoxins in Bivalve Molluscs (Oslo 26 September 2004).

c ) Review the outcome of the WKNCT Workshop on New and Classical Techniques in Enumeration of Phytoplankton.

d ) Review progress towards the joint theme session between WGHABD and WGPBI for the ICES ASC in 2006 titled "Harmful Algae Bloom Dynamics;

Validation of model predictions (possibilities and limitations) and status on coupled physical-biological process knowledge".

e ) Review progress and analyses that REGNS North Sea Group have done on datasets submitted by members of WGHABD (to meet in the interim).

f ) Discuss new findings that pertain to harmful algal bloom dynamics. Bring new findings in phytoplankton population dynamics models, with emphasis on loss processes, to the attention of WGHABD for discussion.

g ) Review the on-line format of HAEDAT submission form and evaluate the amendments made to update historical submissions and links to mapping.

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h ) Review the structure and composition of the decadal HAE maps for the ICES region with special reference to clarifying the distinction between harmful algal blooms and the harmful affects that are reported on the maps. In particular, the registration of cyanobacterial blooms in brackish and marine waters should be re- visited from the emerging perspective of their known toxicity and implicit harmful effects.

i ) Collate and assess National reports and update the decadal mapping of harmful algal events for the IOC/ICES harmful algal database, HAE-DAT (Country Reps).

j ) Discuss and report on potential contributions to the ecosystem overview of the advisory reports describing the quantity and quality of marine habitat and/or the health of the marine ecosystem, and to consider and report on potential indicators of significant change in these ecosystem attributes.

k ) Review and update sub-regional data tables and where necessary include new data (parameters) and/or existing data (parameters) updated where relevant. The data tables will be subject to thematic assessment to be undertaken at a REGNS thematic assessment workshop.

3 Summary and Conclusions

Techniques for analysis and prediction of the population dynamics of HABs are not well developed and measures of species-specific growth rates and mortality rates are very difficult.

Monitoring is an important aspect of HAB research and the WG needs to interact with monitoring programme designs and data interpretation. For example, more environmental data is often needed and sampling should be rationalised with local hydrography such as mixed layer depth, circulation patterns, frontal dynamics, etc. Historical data and time series data from sediment and climate studies are important in looking for historical occurrences of HABs. Increase and decrease in population size is important to bloom dynamics.

The importance of the WG approach and focus on population dynamics of specific HAB species and not on phytoplankton ecology in general was emphasized. The economic, resource and environmental effects of HABs are included within the WGHABD. In addition, phytoplankton ecology models often rely on biomass, nutrient, and carbon cycling and in many cases, cannot define, explain or predict HAB dynamics. In the past we have had joint meetings with modellers to try and incorporate physics and HAB dynamics into models.

The WG felt that the existing ToR were related, and were important to dynamics.

Term of Reference a) Review progress in the detection of harmful algal blooms and their dynamics by remote sensing techniques and examining results from new sensors and algorithms as well as validation procedures used for HAB observations.

Five presentations were made, including a review of current technology followed by presentations of data from Sweden, USA (2) and Canada.

Space – or airborne remote sensing of the sea, sometimes termed EO (Earth Observations) is often motivated with the aim of observing harmful algal blooms. Initiatives including the GMES (Global Monitoring for the Environment and Safety), the MERSEA program and its application to Operational Oceanography and HAB detection in real time will be reviewed.

New satellites and sensors have become operational the last years, i.e., the MERIS sensor on the European satellite ENVISAT and the US satellites AQUA and Terra with the sensor MODIS. Older sensors include the SeaWIFS that has reached its end of life. Earth observations have limitations regarding HAB observations which include that only high biomass blooms are detected, and only surface water is monitored etc.

In general the only HAB-product available is chlorophyll a. Also cloud cover is a problem for the technique. New sensors with higher spatial and spectral resolution as well as new

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algorithms for data processing hold promise for resolving signals for HAB-species or algal groups, e.g., cyanobacteria. There is a great need to review the results from the new sensors and algorithms and the validations procedures used.

The conclusions of these discussions were:

• Use remote sensing data for detection and monitoring of possible harmful algal blooms is possible but should include verification observations with in situ data (traditional, buoys, SOOP, ferrybox, etc.);

• Combination of results with meteorological and oceanographic forecasting models to predict impact;

• Near real time monitoring is useful;

• It is vital to spread the information beyond the science community: to authorities, stakeholders and to the public and the information should be presented in a simple, understandable way.

Term of Reference b) Review the section on Phytoplankton Monitoring in the Report of the Joint FAO/IOC/WHO Ad Hoc Expert Consultation for Codex Alimentarius on Biotoxins in Bivalve Mollusks (Oslo 26 September 2004).

This report was in response to requests from countries for updated guidelines for biotoxin analysis methods and regulator thresholds and plankton monitoring

The draft report was distributed at last year’s WGHABD for comments and Per Anderson presented a summary of the guidelines in the report.

Term of Reference c) Review the outcome of the WKNCT Workshop on New and Classical Techniques in Enumeration of Phytoplankton.

This workshop was a complex activity requiring algal cultures, field material and a variety of different methodologies, with the objective of providing valuable results on the comparison of different microscope based techniques and some advanced molecular techniques for the identification and quantification of harmful microalgae. The WGHABD was instrumental in initiating this process and established a steering committee. The steering group presented a summary of the report from the workshop and discussed its dissemination.

Term of Reference d) Review progress towards the joint theme session between WGHABD and WGPBI for the ICES ASC in 2006 titled “Harmful Algae Bloom Dynamics; Validation of model predictions (possibilities and limitations) and status on coupled physical-biological process knowledge”.

An update on this theme session was provided by one of the co-conveners with input from the working group.

Term of Reference e) Review progress and analyses that REGNS North Sea Group have done on datasets submitted by members of WGHABD (to meet in the interim).

The REGNS study group has requested that the WGHABD prepare to provide data, information and indicators. A delegate from the WGHABD reported on the outcome of the REGNS meeting in May 2005 and on the progress of the assembly and analysis of the data.

Term of Reference f) discuss new findings that pertain to harmful algal bloom dynamics.

Bring new findings in phytoplankton population dynamics models, with emphasis on loss processes, to the attention of WGHABD for discussion

The working group received nine presentations on new findings and events, from the participants. These included the Summary of a project on the Biological Oceanography of HABs in Ireland, A review of a Nodularia model, review of the FlowCam system in cell

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enumeration, Spirolide Neurotoxins from Alexandrium ostenfeldi,. An exceptional bloom of Karenia mikimotoi in Ireland, The 2005 New England Alexandrium fundyense bloom, Azaspiracid in crabs, Dinophysis in the Swedish Skagerak and Alexandrium cell abundance in the Bay of Fundy.

Modelling exercises aimed at understanding HAB population dynamics have suffered from poor estimates of biological loss terms. Current knowledge on selected HAB loss processes (e.g., grazing, viruses, parasitism, and programmed cell mortality) is limited. Improved knowledge on the dynamics of these loss processes and their relative contribution is essential to improve models for HAB dynamics. Of the presentations received dealing with population dynamics of HABs there still was a concentration on the onset of blooms rather than their fate, there appears to be little information being generated on the loss processes.

Term of Reference g) The new online format of the HAE-DAT submission form was demonstrated and discussed. The suggestions from last year’s discussions at WGHABD have been mostly incorporated and the dataset is in a format where better analyses can be conducted. This new format replaces the previous where data was entered manually into the HAE-DAT dataset (which was in Access97 format). This new electronic format (with the same information as previous forms) is available online for submission directly into the database. Monica Lion (IOC-IEO-SCCHA, Vigo, Spain) has gone through potential problems for the conversion of all the old historical records into the new form.

Term of Reference h) Review progress in computerized production of decadal maps from country reports, including the revision of reports already in the database covering the last 10 years Decadal maps are currently being updated manually. A new Decadal maps product which uses both ArcView and Flash softwares, and allows updating of maps from a MySQL database is being explored. The use of the MySQL database both in the new HAEDAT format and in the new decadal maps will open future technical options for linking these two datasets that will be studied during this year. The capability of linking the maps has been and continues to be extended to additional countries. Most ICES member countries have provided divisions of coastlines and coordinates to enable the linkages. Further opportunities to develop the links will be explored inter-sessionally.

Term of Reference i) Collate and assess National reports and update the decadal mapping of harmful algal events for the IOC/ICES harmful algal database, National reports were presented for, USA, Germany, Denmark, Canada, Norway, Estonia, Latvia, Poland, Netherlands, Great Britain, Ireland, Spain. Maps were circulated for updating for inclusion to the decadal maps. Information was requested for input on the new online database in the required format for HAEDAT.

Term of Reference j) It was concluded that that the role of phytoplankton with regard to the ecosystem approach, is a far wider issue than could be addressed by WGHABD, whose main role is to investigate the dynamics of functional sub-group of phytoplankton. If the Oceanographic Committee wish any specific advice on this matter the group would be happy to discuss this inter- sessionally.

Term of Reference k) Dealt with under ToR e).

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4 Term of Reference a)

4.1 Monitoring possible harmful algal blooms from satellite - review of recent developments and applications

Martin Hanson from the Swedish Meteorological and Hydrological Institute - SMHI Oceanographic Unit, Göteborg, Sweden opened this term of reference with a review of orbiting sensors and their application in the HABs area.

The advantages of Satellite sensing of HABs were described to include the fact that they offer a unique synoptic view of large areas of the oceans and provide regular monitoring (during cloud free conditions) repeat cycle about 0.5–6 days. They also show position of favourable blooming areas, ocean fronts upwelling, advection of water masses. (SST) and can improve model predictions. Other information such as inter-annual variability on extent, duration and occurrence can be mapped. When a HAB event has been confirmed with in situ measurement it is possible to monitor movements and development. In effect, remote sensing of HABs in combination with in situ monitoring and models result can be used as an efficient monitoring and prediction system.

However, certain disadvantages were also pointed out including HAB events must always be confirmed by in situ measurement, it is difficult to distinguish between species and also between other properties of the water; yellow substance, particles, etc. HABs usually occur in coastal waters where the rfesolution form satellites is poor, and

HABs are often present in too small amount to be detected but enough amounts to cause problems. Satellites rely on HABs being present in the surface layer, and also rely on cloud free conditions

A selection of applications using satellite derived data were presented:

Some notable applications included the Gulf of Mexico Harmful Algal Bloom Bulletin (Figure 4.1.1). In the Gulf area, harmful red tides (Karenia brevis) frequently occur and these can cause death to fish, birds and marine mammals. In addition eating shellfish from contaminated waters can cause NSP. Since 1999, Harmful Algal Bloom Bulletins have been issued by NOAA´s National Centers for Coastal Ocean Science (NCCOS) to help coastal environmental managers Information and conclusions are based on satellite data (SeaWiFS), in situ measurements, models, wind observations Bulletins are issued frequently (once or twice a week)In South Africa a joint effort between the University of Cape Town, Marine and Coastal Management and the Benguela Current Large Marine Ecosystem (BCLME) programme provides near real time HABs information on a website (http://www.hab.org.za). The Benguela system is characterised by upwelling circulation along the entire west coast of southern Africa HABs are common, one or another dinoflagellate species and are associated with either high biomass or the toxicity of some species. Impact on both commercial and recreational interests, causing fish kills, contaminating seafood with toxins resulting in serious public health problems, or altering ecosystems.

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Figure 4.1.1: Gulf of Mexico Harmful Algal Bloom Bulletin.

The Baltic Algal Watch System (BAWS) has been operational since 2002. This system produces daily map of extent of surface accumulation during bloom season. It is based on satellite data (NOAA-AVHRR and MODIS). An integrated web presentation for environmental managers and a public web site are available (www.smhi.se). The website provides information on bloom coverage, near real-time information, weather forecasts, model results, seatrack-web (Forecasts and dispersion of oil and chemicals, including surface accumulations of cyanobacteria) and incoming solar radiation.

4.2 Detection of harmful algal blooms and their toxins by in situ and remote techniques

Allen Cembella gave a useful overview of developments in the field of in situ and remote sensing of HABS

A wide array of emerging technologies have been developed within the last decade to specifically address the problem of detection and quantification of harmful algae and their toxins. Classical methods for cell enumeration and species identification are hampered by the requirements for a high level of taxonomic expertise, the time constraints imposed by tedious (and thus perhaps erroneous) manual counting and the difficulties of interpreting the results of point-source discrete sampling in long-term monitoring programmes. For example, discrimination of the various members of the genus Alexandrium by morphological criteria with microscopic methods generally involves careful study of diagnostic features (presence/absence and shape of the ventral pore; morphology of the apical pore complex) of individual cells, often with the aid of fluorochrome staining. Similarly, the diagnostic features of many species of the diatom genus Pseudo-nitzschia (e.g., arrangement and number of poroids on the valves) are at the limits of resolution of the light microscope and therefore misidentification at the species level is undoubtedly common.

From the perspective of phycotoxin assays and analysis, there are also urgent requirements for supplanting conventional whole-animal bioassays such as the AOAC mouse bioassay with more precise and refined methods for individual toxins or groups of toxins with a common mode of action. In both cases, it is desirable to move towards implementation of methods that offer real-time and continuous data on harmful taxa and their respective toxins for field deployment in monitoring programmes.

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Deployable systems for bloom and toxin monitoring should be developed to fulfil three basic niches: surveillance, operational aspects and investigative requirements. Surveillance implies the ability to survey the target sites and regions of interest with the objective of providing information on early warning of impeding blooms, as well as on the subsequent stages of the bloom development cycle – including both qualitative and quantitative data. The operational elements refer to the function and integration of the technology into workable systems for field deployment, involving data acquisition and retrieval, use of the appropriate algorithms and calibration procedures, networking and reliability (e.g., with respect to biofouling), sensitivity, precision and accuracy of the measurements. As investigative tools, the systems should be amenable to incorporation into field-based research programmes on bloom dynamics and mechanisms of toxin propagation in marine food webs.

Field systems based upon general biooptical principles (fluorescence, spectral absorption, optical back-scatter, etc.) are best suited for detection and monitoring of high biomass HAB blooms, especially where the taxon of interest has a unique optical signature and where the bloom approaches monospecificity. By comparison, taxon- and toxin-specific methods will also work for low biomass blooms and complex assemblages where the target species may be dispersed and in low abundance. Among the taxon-specific probe methods, techniques based upon molecular targets at the cell surface (e.g. lectins, antibodies), in cell membranes, and moieties of intracellular proteins, nucleic acids and nuclear genes have proven to be most useful. As detection systems, many platforms, such as ELISA plate assays, epifluorescence microscopy, flow cytometry, and molecular approaches involving sandwich hybridization assays of extracted RNA and PCR-based methods have been successfully applied in the laboratory but most of these techniques have not been adapted for field deployment. Among the laboratory methods, fluorescence in situ hybridization (FISH) coupled with epifluorescence microscopy, flow cytometry or solid-phase support cytometry (Chemscan) are among the most advance and widely employed for species discrimination. Operational field- deployable systems are at present limited to the Environmental Sample Processor (ESP) developed at Monterrey Bay Aquarium, which employs a custom-printed oligonucleotide probe array to detect taxon- specific rRNA molecules by the principles of sandwich hybridization. An image of the resulting array is recorded using the CCD camera. An alternative system, developed from a prototype of a hand-held electrochemical detector (Inventus BioTech, Germany) is based upon detection of specific 18 rRNA sequences attached to a reporter probe and digoxigenin to generate an electrochemical signal. This system has been further developed to incorporate a multiprobe chip for simultaneous detection of 14 taxa in flow-through mode (Palm Sense, Germany); the intention is to incorporate this into a field system for cell-based detection (e.g. CytoBuoy, Netherlands).

In situ and portable ship board systems are particularly useful in monitoring and bloom dynamic studies in small-scale coastal embayments where the horizontal and vertical patchiness of the blooms renders satellite-based surveillance largely ineffective. Even the most advanced satellite-based optical sensors (SeaWifs, MODIS, etc.) have a minimal patch size of several hundred square metres and cannot provide data from below the surface, on cloudy days, or continuously. Aircraft-transported spectral sensors, such as CASI – compact airborne spectrographic imager – have been used successfully to map chlorophyll distribution and concentration with a spatial resolution of several metres with several meters of vertical penetration even in coastal waters, but again they cannot be used continuously or in poor weather. Such systems provide only limited taxonomic information based on spectral signature.

Developments in biooptical buoys, including for example the tethered attenuation coefficient chain sensor (TACCS) from Satlantic, offer the opportunity to continuously monitor the diffuse attention coefficient by spectroradiometric measurements – essentially a measure of ocean colour and the underwater light field. New hyperspectral sensors now provide more

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information on the discrimination of phytoplankton pigment signatures as distinct from seston and CDOM but cannot resolve the profiles of individual species or in most cases even taxonomic groups (e.g. diatoms versus dinoflagellates) in complex assemblages without a dominating taxon. This technology is ideally used in conjunction with more cell-specific detection systems as a coordinated package.

It is now possible to conduct surveys of toxin profiles in the water column with on board liquid chromatography mass-spectrometry (LC-MS) systems. Underwater mass spectrometers do exist but thus far the marine toxins of interest cannot be detected with this technology.

Nevertheless, such developments can be anticipated in the next few years.

References

Anderson, D.M., and Cembella, A. 2002. Probe Technologies. In Report of the ICES Working Group on Harmful Algal Bloom Dynamics, Bermuda, 7–10 March 2002, ICES CM 2002/C:03. International Council for the Exploration of the Sea, Copenhagen, pp. 19–30.

Cembella, A.D., Doucette, G.J., and Garthwaite, I. 2003. In vitro assays for phycotoxins. In Manual on Harmful Marine Microalgae, Monographs on Oceanographic Methodology.

Ed. by G.M. Hallegraeff, D.M. Anderson, and A.D. Cembella. UNESCO, Paris, 11: 297–

345.

Cullen, J.J., Ciotti, A.M., Davis, R.F., and Lewis, M.R. 1997: Optical detection and assessment of algal blooms. Limnol. Oceanogr., 42: 1223–1239.

Dickey, T.D., and Moore, C. 2003. New sensors monitor bio-optical/biogeochemical ocean changes. Sea Technology, October.

Scholin, C.A., Doucette, G.J., and Cembella, A.D. 2006. Prospects for developing automated systems for in situ detection of harmful algae and their toxins. HABWatch, Monographs on Oceanographic Methodology. Ed. by M. Babin, C. Roesler, and J.Cullen. UNESCO, Paris, in press.

4.3 Regulation of alongshore Alexandrium transport in the Gulf of Maine USA

Don Anderson reported on developments in the use of AVHRR imagery rather than ocean colour imagery to detect conditions conducive to bloom development and transport in a Gulf of Maine Alexandrium event in 2005.

Many applications of remote sensing technology to HAB detection and tracking rely on ocean colour. There are locations, however, where HAB species do not make up a significant proportion of the plankton, and thus where pigment signatures cannot be used for detection.

Alexandrium fundyense blooms in the Gulf of Maine are an example of this situation.

Nevertheless, remote sensing technologies can be useful in management of paralytic shellfish poisoning (PSP) events – in this instance through a focus on sea surface temperature. In a recent paper by Luerssen et al (2005), relationships between satellite-derived sea-surface temperature (SST) patterns and the occurrence of PSP toxicity events caused by A. fundyense in the western Gulf of Maine were examined. Comparison between surface cell distribution patterns and SST images indicates that highest cell concentrations are associated with colder waters of the eastern segment of the Gulf of Maine coastal current (EMCC) and that frontal zones at the edges of the EMCC often act as boundaries to surface distributions. Surface thermal patterns can reveal enhanced connectivity between the EMCC and the western Gulf of Maine, suggesting transport linking A. fundyense cells in the EMCC to inshore areas of the western Gulf of Maine. Surface drifter data support such transport. Thirteen years (1990–

2002) of toxicity data from eight monitoring sites along the coast of Maine and concurrent SST data show that in years of either large or very-reduced toxicity, a consistent relationship exists between the timing and strength of fronts, calculated from the SST data and taken as an

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indicator of alongshore connectivity, and the occurrence and strength of toxic events. Years with weak fronts and/or fronts that become established relatively late in the summer growing season are years of the strongest toxicity events in western Gulf of Maine. Years of early and strong fronts are years with few and/or weak toxicity events. These results point to the utility of SST and other coastal observing system data for the monitoring and prediction of conditions linked to toxic events in coastal waters.

References

Luerssen, R.M., Thomas, A.C., and Hurst, J. 2005. Relationships between satellite-measured thermal features and Alexandrium-imposed toxicity in the Gulf of Maine. In The Ecology and Oceanography of Toxic Alexandrium fundyense Blooms in the Gulf of Maine. Ed. by D.M. Anderson, D.W. Townsend, D.J. McGillicuddy, Jr., and J.T. Turner. Deep Sea Research Part II: 52: 2656–2673.

4.4 HAB forecast for Karenia brevis in the Gulf of Mexico

Pat Tester described the utilisation of chlorophyll anomaly in the Gulf of Mexico to identify HABs of Karenia Brevis.

The HAB forecast for Karenia brevis in the Gulf of Mexico is based on ocean colour satellite imagery and is possible, in part, due to the lower backscatter of K. brevis compared to blooms of diatoms or Trichodesmium spp. (Carder and Steward 1985). Stumpf et al. (2003) suggested a simple chlorophyll anomaly might be useful to detect and monitor K. brevis. They developed a forecast model based on a 60-day running mean of chlorophyll when diatom and Trichodesmium spp. were not indicated. An anomaly is the difference in chlorophyll value per pixel between the image of interest and the 60-day running mean for the same pixel mean (lagged by 14 days to avoid the influence of a new bloom on the chlorophyll mean) (Figure 4.1.1). This was the first step in an early warning system to forecast K. brevis blooms in the eastern Gulf of Mexico and was available as an experimental product form 2001 to 2003 when the HAB forecast became operational on a regular basis with the frequency depending on the intensity of Karenia brevis blooms (http://coastwatch.noaa.gov/hab/bulletins). The bulletin also includes wind speeds and directions so potential surface movement of the blooms under the influence of the wind field can be judged. This forecast was evaluated (Tomlinson et al.

2004) and found to be accurate >83% of the time. There are plans to expand this forecast into the northern Gulf of Mexico in late 2006.

Figure 4.4.1: Harmful algal bloom forecast for Karenia brevis in the Gulf of Mexico is based on chlorophyll anomaly. A. 3 August–3 September 2001 Sixty-day running mean for each pixel in image. B) An anomaly is the difference in chlorophyll value per pixel between the image of interest and the 60-day running mean lagged by 14 for the same pixel in the image of interest. Anomalous chlorophyll values of 1 ug/L. are flagged in red. See Stumpf et al. 2003.

Tampa Bay

A Tampa Bay B

A B

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References

Carder, K.L., and Steward, G.R. 1985. Remote-sensing reflectance model of a red-tide dinoflagellate off west Florida. Limnology and Oceanography, 2: 286–298.

Stumpf et al. 2003. Monitoring Karenia brevis blooms in the Gulf of Mexico using satellite ocean color imagery and other data. Harmful Algae, 2: 147–160.

Tomlinson et al. 2004. Evaluation of the use of SeaWiFS imagery for detecting Karenia brevis harmful algal blooms in the Gulf of Mexico. Remote Sensing of the Environment, 91: 293–303.

4.5 Alexandrium measurements using remote sensing in Grand Manan Island in Bay of Fundy

Jennifer Martin showed an example where ocean colour imagery should be treated with caution. In 2003 highest cell counts of Alexandrium were not reflected in ocean colour (Modus or SEAWiFS) 888,000 cells/L in the next year with up to 4M cell/L still not able to tease out signal from ocean colour imagery

The presentation demonstrated with series of ocean colour images – areas of high chlorophyll that did not match where the high cell counts were recorded. It was noted that the variability between sea surface chlorophyll and high cell counts may not coincide due to mixing of the upper levels of the water column.

Figure 4.5.1: Chlorophyll concentrations in the Bay of Fundy 2003.

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5 Term of Reference b)

5.1 Phytoplankton Monitoring in the Report of the Joint FAO/IOC/WHO Ad Hoc Expert Consultation for Codex Alimentarius on Biotoxins in Bivalve Mollusks

(Oslo 26 September 2004).

Per Anderson gave a presentation on the section of the Report. This expert working group was made up of the following scientists who convened to draft guidelines for FAO/WHO/ IOC.

Expert Panel:

Dr Per Andersen, Bio/Consult, Denmark

Prof Tore Aune, Norwegian School of Veterinary Science, Norway

Dr Daniel G. Baden, University of North Carolina Wilmington, United States of America Mrs Catherine Belin Ifremer Centre de Nantes, France

Prof Luis Botana, Univ. Santiago de Compostela, Spain

Mr Phil Busby, New Zealand Food Safety Authority, New Zealand

Dr Bob Dickey, US Food and Drug Administration, United States of America Dr Valerie Fessard, French Food Safety Agency (AFSSA), France

Prof Lora E. Fleming, University of Miami, United States of America Mr John Foorde, Marine and Coastal Management, South Africa Dr Jean-Marc Fremy, French Food Safety Agency (AFSSA), France

Dr Sherwood Hall, US Food and Drug Administration, United States of America Dr Philipp Hess, Marine Institute, Ireland

Dr Patrick Holland, Cawthron Institute, New Zealand Dr Emiko Ito, Chiba University, Japan

Dr Tine Kuiper-Goodman, Health Canada, Canada Dr Jim Lawrence, Health Canada, Canada

Mr David Lyons, Food Safety Authority of Ireland, Ireland Dr Rex Munday, AgResearch, New Zealand

Prof Yasukatsu Oshima, Tohoku University, Japan Dr Olga Pulido, Health Canada, Canada

Dr Michael Quilliam, National Research Council, Canada

Prof Gian Paolo Rossini, Universita di Modena e Reggio Emilia, Italy Prof Michael Ryan, University College Dublin, Ireland

Dr Covadonga Salgado, Centro do Control do Medio Marino, Spain Mr Joe Silke, Marine Institute, Ireland

Dr Gerrit I.A. Speijers, National Institute of Public Health and the Environment, the Netherlands

Dr Benjamin Suarez-Isla, Universidad de Chile, Chile

Dr Toshiyuki Suzuki, Tohoku National Fisheries Research Institute, Japan Dr Andy Tasker, University of Prince Edward Island, Canada

Dr Hans P.van Egmond, National Institute of Public Health and the Environment, The Netherlands

Dr Phillippe J.P. Verger, Institut National Agronomique Paris-Grignon, France Prof Takeshi Yasumoto, Japan Food Research Laboratories, Japan

Working group 3: was a sub-group tasked to draft guidelines on growing area management and monitoring

Working Group 3 Members

Per Andersen , Catherine Belin, Phil Busby (Chair), Henrik Enevoldsen, John Foord, David Lyons, Yolanda Pazos, Joe Silke, Covadonga Salgado

Task: Provide Guidance on Growing Area Management and Monitoring

1 ) Provide guidance on sampling methods for shellfish, including sampling depths, sample size, representative sampling, frequency of sampling

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2 ) Provide guidance on the use of phytoplankton monitoring (strengths and weaknesses) as part of a shellfish marine biotoxin program

3 ) Provide guidance on indicator organisms for the different toxin groups

4 ) Provide information on the existence of biotoxin forming marine algae in various geographical regions of the world

5 ) Provide guidance on phytoplankton laboratories, accreditation, training of analysts, counting methods etc

6 ) Provide guidance on marine biotoxin management plans, including micro management

7 ) Provide guidance on environmental/hydrographic/oceanographic influences in growing areas

8 ) Provide guidance on sampling, including location of sample stations, sample size, use of indicator organisms, training of samplers, frequency of sampling, sample collection methods, transport of samples

9 ) Provide guidance on reporting, release and exchange of data

The Role of Micro-Algal Monitoring in Marine Biotoxin Management Micro-algae (including planktonic and benthic organisms) are the primary source of biotoxins in bivalve molluscs. A marine biotoxin management programme should be described in a marine biotoxin management plan (MBMP). The MBMP should include marine biotoxin action plans (MBAPs) for growing areas containing, for example, sampling strategy and requirements (frequency, sample size and composition), analyses to be carried out, and management action to be based on monitoring results and expert judgment.

Toxicity monitoring cannot be replaced solely by micro-algae monitoring. Information from micro-algal monitoring, especially if it is carried out regularly (for example weekly during harvesting), as part of a bivalve mollusc biotoxin management program, has particular strengths, including:

• Generally, observable concentrations of toxic micro-algae precede critical levels of toxins in bivalve molluscs and, therefore, allows management options to be considered, such as:

• Precautionary closures;

• Intensified monitoring or depth-specific sampling.

• Micro-algal monitoring can also help focus shellfish testing, for example on likely toxins, at the right location, at the appropriate time and when new toxin- producing species of micro-algae are found in an area.

• Micro-algal monitoring as part of an integrated biotoxin management program, is cost effective and operationally efficient.

• It may be used to investigate unknown, unusual or atypical toxic events.

• It may be used to provide information to set or use switching factors. These may activate associated management options.

• It may provide information not only on the onset of a toxic event but on the duration of any intensified management action.

Therefore, for early warning purposes and direct risk management activities it is recommended to have a program to monitor growing areas for species of toxin-producing micro-algae. The program should also include evaluation of other environmental conditions, for example wind, water temperature and salinity, which may suggest upwelling, stratification or mixing. These conditions may indicate that favourable conditions for a toxic event are developing.

However the weaknesses of such a system may include:

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• Micro-algal observations may not accurately reflect the actual level of toxins in shellfish. In part this may be due to significant inter- and intra-species variability in toxin profile and toxin content for many micro-algal species even from the same area and over a short period.

• While micro-algae are the primary source of toxicity in shellfish, the toxins may remain in shellfish long after the toxic micro-algae are gone. Thus, the absence of toxic micro-algae cannot be taken as an indication that the shellfish are safe.

• Micro-algae are not always distributed uniformly in either time or space.

“Patchy” distribution of micro-algae may make representative sampling difficult.

• The logistics of sampling offshore or remote areas, where scallops or clams for example are fished, may make micro-algal monitoring less cost effective.

• Special monitoring arrangements may be necessary to address the problems posed by benthic species of toxic micro-algae, for example Prorocentrum lima.

In conclusion, decisions made on the safety of shellfish can only be based on the direct measurement of toxins in shellfish flesh. However, an integrated shellfish and micro-algal monitoring programme is highly recommended to provide expanded management capability and enhanced consumer protection.

Furthermore, recent developments indicate that micro-algal monitoring coupled with operational oceanographic, meteorological, and remote sensing data, including modelling and other measurements may be used to base advice on the imminent onset of harmful events.

6 Term of Reference c)

6.1 A summary of the intercalibration workshop on cell counts held in Kristinaberg

Presented by Bengt Karlson, Caroline Cusack and Eileen Bresnan.

This workshop was held to compare traditional and novel methods for counting cells under controlled conditions, in order to attempt to identify the state of the art with regards to cell enumeration. The following objectives were set to be addressed by the workshop:

• Used Alexandrium ostenfeldii and A. fundyense;

• Examine traditional microscope methods for cell abundance to determine if traditional and molecular or new methods would provide comparable results;

• Is there one method that can be recommended?

• Used nine traditional methods, eight molecular methods and FlowCam, 100 ml used for all:

• Utermohl’s, settling bottle, counting chambers;

• Molecular techniques used different versions and different personnel.

Bengt summarized findings

Generally the counting chambers with the small volumes were less reliable at low cell concenrations. At 500 cell/L results somewhat more consistent. Samples were fixed and sent to Canada to J. Martin’s lab for FloCam analyses. In experiment 4 the numbers were in good agreement.

Problems observed:

• Time constraints;

• Limited sample volume;

• Aberrant cells from cultures observed;

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• Some labs not perfect for molecular biological work;

• Not correct temp in incubation ovens;

• Some methods were not properly calibrated for the material used.

Did not test:

• Total phyto community;

• Biomass;

• Other species that target.

Results:

• Short report distributed on ICES website;

• Scientific article to Harmful algae;

• IOC Manuals and Guides – A practical guide to quantitative phytoplankton analyses.

Conclusions: Successful:

• 24 participants from three continents;

• 18 methods for quantitative phytoplankton analysis were compared;

• Approx 1000 samples were made up and analyzed;

• Inter comparison focused on only one species A. f.

Financial support was acknowledged from IOC, BIM Ireland, and Marine Institute Ireland.

SMHI Kristineberg Marine Research Station supported lodging.

Comments:

• A discussion of the workshop followed It was felt that the expectation was that traditional methods would not be good at identification of cells but would be better at enumeration. As it turned out this was not really the case, however, some the traditional methods were not as good at cell ID as expected. Some of the molecular methods were better at enumerating cells than expected;

• It was pointed out that one did not really have a big challenge in cell identification – and that this was the best case scenario and any natural samples would have greater error;

• Overall the working group said that the exercise was successful. Some of the tests were under some constraints. – Molecular techniques were difficult to set up – needed more lead time than microscope;

• The organizers were commended for their fine work in setting up and conducting a successful workshop.

7 Term of Reference d)

7.1 Update on the ASC theme session entitled “Harmful Algae Bloom Dynamics: Validation of model predictions (possibilities and limitations) and status on coupled physical-biological process knowledge”

The Annual Science Conference will host a theme session jointly convened by Patrick Gentien (France) and Tapani Stipa (Finland). Dr Gentien provided information on this session for the working group.

In spite of large gaps of basic process knowledge around HAB dynamics, several 3-D modelling initiatives are ongoing with respect to studying and predicting HABs. Therefore it

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is due time to couple the expertise of modellers and biologists to reveal the most urgent needs for better process knowledge to improve the predictability of models. The Session aims at participation from 3-D modellers and biologists (including invited contributions from GEOHAB) interested in explaining:

• Why HABs occur,

• How HABs are initiated,

• How and why HABs develop in space and time,

• Why HABs decay and to demonstrate:

• Existing 3-D modelling capabilities,

• Status on validation of such models,

• The need for observations (satellite and in situ).

The working group asked that a review of this theme session would be presented at the 2007 WGHABD.

8 Term of Reference e)

8.1 Review progress and analyses that REGNS North Sea Group have done on datasets submitted by members of WGHABD (to meet in the interim)

Einar Dahl presented an update on progress on datasets and analysis by REGNS Integrated Ecosystem Assessment of the North Sea – An ICES Pilot Project.

Objectives:

1 ) Look at ways in which the existing ICES structure (data centre & working groups) can input into the periodic production of regional integrated assessment.

2 ) To deliver a pilot Integrated Assessment (not advice) on the North Sea Ecosystem by September 2006.

North Sea – hope to get information from a variety of working groups – HABS related to eutrophication is the preferred data set for this assessment. Ended up with data from five different sources

• Plankton recorder, chl;

• Physical data;

• Fish landing by species;

• Sea birds;

• Fish assessment.

HAB data might go back to early 1980s and therefore care must be exercised in incorporating these data sets to ensure region specific artefacts are not incorporated. What is needed is REGNS gridded data for analyses and spatial and time series and for HABs most data is collected by regional programmes rather than on a wider geographical scale.

The presentation demonstrated specific areas were identified with PCA and mapped those regions that clustered together on PCA.

Conclusions: Clear gradients were evident in space and time. State changes were seen in 1988 but also in 1965 and 1979. The cause appears to be related to Sea water flux into the Northern

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North Sea The weight given to the different parameters needs investigation – not all parameters are of equal ecological significance – expert input required. Sub-regions could be defined and the thematic assessment undertaken – now asking if HABS could fit in to the assessment. The working group felt that that the HAB data sets might be too short to be useful but perhaps some sources may have long data.

It is hoped that the value of undertaking this type of integrated assessment would be to help the future design of monitoring programs and the setting of realistic policy targets for management purposes

Lessons learned:

• Took time to understand the concept and definitions different user needs;

• Identify data sources was easy but not easy to access;

• Value action gap too many vested interests;

• Data gathering and checking not complete;

• New methods for analysis required still.

This work is not yet complete; however the preliminary overview assessment is the source of the existing information. A further meeting of the Regional Ecosystem Study Group for the North Sea (Chair: A. Kenny, UK) will meet at ICES Headquarters from 15–19 May 2006 to:

a ) Hold a workshop to evaluate and plan the finalization of the 2006 integrated ecosystem assessment for the North Sea, to be presented at the 2006 ASC;

i ) review the outcome of the work of an intersessional correspondence group (sub-group of REGNS) with compilation and analyses of a comprehensive integrated data set for different aspects and components of the North Sea ecosystem;

ii ) review the outcome of intersessional work on relating state variables of the ecosystem with human pressures according to themes (eutrophication, pollution, conservation, fisheries, climate, and management);

iii ) prepare plans for finalization of the integrated ecosystem assessment which must take account of the relationship between the thematic human pressures assessments (in ii above) and the overview integrated assessment (in i) above);

iv ) prepare for presenting the outcome of the integrated ecosystem assessment at the 2006 ICES Annual Science Conference;

b ) Advise on follow-up work to translate the experiences of REGNS in producing an integrated ecosystem assessment into a regular process in ICES of producing or contributing to the production of updated integrated assessments for the North Sea ecosystem;

c ) Based on the experience with the production of the 2006 North Sea integrated assessment; consider requirements that need to be taken into account in a design of a holistic monitoring of the North Sea ecosystem.

REGNS will report by 30 June 2006 for the attention of the Resource Management Committee, ACFM and ACE.

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9 Term of Reference f)

9.1 New findings that pertain to harmful algal bloom dynamics:

9.1.1 BOHAB

Joe Silke and Caroline Cusack

Biological Oceanography of HAB species in Ireland

The National University of Ireland, Galway, Woods Hole Oceanographic Institute and the Marine Institute carried out a research programme entitled The Biological Oceanography of Harmful Algal Blooms (BOHAB) between 2003 and 2005. The primary objective of this work was to collect physical and biological information, which is associated with the generation of Harmful Algal Blooms (HABs) in Irish waters. Using this information the project worked towards the production of a predictive tool, which could potentially be used to mitigate the effects of these economically damaging events. The west of Ireland supports the bulk of Irish aquaculture activities. The two most important aquaculture areas in this region were chosen to carry out the detailed part of the research, Killary Harbour and Bantry Bay.

The Irish aquaculture industry has become a vital part of Irelands coastal economy since its initial development in the early 1970s. The diversity of sites used and the species farmed have also increased. The sector grew in output value from €37.2 million (26 500 tonnes) in 1990 to a peak in 2002 of €125 million (61 000 tonnes). Unfortunately there have been several protracted occurrences of Harmful Algae that have slowed down the development of the industry, and in some cases have been responsible for major mortality of stock and intoxication of shellfish.

HABs in Ireland have caused the greatest impact on shellfish farms, but have also been responsible for mortalities on caged finfish farms. Mussels, Pacific oysters, Native oysters, clams and scallops are the main shellfish species being produced in Ireland at present.

Mussels, which are farmed using both suspended ropes (intensive) and bottom-culture (extensive), account for 80–90%, by volume, of annual shellfish production. Oysters (principally Pacific oysters) account for a further 10–15%. Shellfish farming is practised in every coastal county with the exceptions of Wicklow and Dublin. Shellfish species farmed on a smaller scale include abalone and purple sea-urchins.

From the point of view of shellfish producers who are on the front line of HABs, there is a requirement for a rapid and accurate response to the problems associated with algal blooms through a robust means of monitoring and management in order to protect their industry. In addition the prediction of closures due to HABs is important to schedule operational and marketing activities.

It is essential that these basic principles be in place for the development of the industry because the parallel objectives of providing consumer safety and development of the industry are top priorities. The emphasis on researching the means for early warning of the onset, intensity and duration of toxic events therefore are critical for to putting these management strategies in place, and this was the key component of this project.

The themes of the work proposed in this project were chosen to assimilate the knowledge obtained through the scientific aspects of monitoring programmes and oceanographic research, and to gather necessary information that may be used in the design of a predictive model of the onset, intensity and duration of a HAB event.

It was recognised that our understanding of oceanographic processes, in particular the physical processes which directly affect phytoplankton composition and dynamics, may be used to

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develop early warning capabilities. Forexample, research over the last decade has shown that temperature of the water column taken at several depths is a good indicator to measure water and phytoplankton exchange events. The deployment of a simple thermistor string in certain southwest sites is therefore adequate to give fundamental information on potential HAB events. Further biological information on the uptake of toxic plankton by shellfish and the kinetics of toxicity were studied to understand the system so that a basic level of predictive modelling/forecasting can be achieved.

Building upon the BOHAB themes, a common research objective for producers and regulators should be a preventative approach to fish mortalities and shellfish toxicity. Real-time management could complement existing aquaculture and water quality monitoring programmes using agreed standard assessment methods, tools and indicators throughout the EU.

A holistic approach to the management of shellfish toxins has been used in Ireland in recent years. It incorporates the results of bioassay, toxin chemistry, phytoplankton presence, spatial and temporal factors such as high-risk time of year and status of neighbouring areas. This has been used to recommend voluntary action by the industry. The current management of harmful phytoplankton is, however, for the most part, put in place once a bloom is present in an aquaculture area. In some cases fish mortalities or toxic shellfish have already been harvested. Mitigation and prevention of the harmful effects rely on being in a position to predict the onset of a bloom.

One means of attempting this is to look at the relationship between climatic events, changes in phytoplankton composition, and the occurrence of harmful events.

Using this approach, a simple model of the onset of Shellfish Toxicity in the South West of Ireland has been attempted during BOHAB. This is based on the current and forecasted meteorology and time of the year. This model only applies to the SW due to the alignment of the bays in this area, and the fact that there are many years of phytoplankton and toxicity data to develop and test the model. It is, however, intended to research the potential for this approach to be adopted in other bays around Ireland.

From historical records, it can be seen that most of the toxic events in the South West have been preceded by an initial easterly wind, reverting back to the predominant south-westerly wind. When a population of potentially toxic phytoplankton are present, these conditions can allow the passage of these blooms into the bays of the southwest where they can cause toxicity problems. The coupling of these oceanographic events with the biological pathways of harmful algal events is the most promising approaches to predicting the onset of blooms.

BOHAB has made considerable progress in assimilating data and studying the nature of HABs in Irish waters. Future studies can benefit through provision of essential baseline data and a conceptual framework to continue the task of generating a robust and accurate predictive model for HABs and improve the potential for aquaculture in Ireland’s coastal waters.

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9.1.2 Flowcam in Phytoplankton enumeration Jennifer Martin

Advantages

1 ) When using a FlowCAM for phytoplankton enumeration the amount of manual labor in sample processing/handling is greatly reduced. The operator set up to begin a run, but only occasionally monitors it while the FlowCAM is running and detecting particles as pass they through the flow cell.

2 ) The FlowCAM provides a “non-biased” digital record of every particle within a specific size range (determined by the operator) for future analysis. With a traditional microscope, the operator looks as seeks out the particle of interest – providing a biased count of a sample (depending on operator identification knowledge). With the data generated by the FlowCAM each particle is archived and if problems arise the data/images for each particle and/or cell can be re- analyzed at a later time. In the case of this intercalibration study, other species that were present in the sample could also be identified and enumerated, such as, Dinophysis, Protocentrum, Ceratium, heterotrophic dinoflagellates and some nauplii.

3 ) In addition to an image for each particle detected by the FlowCAM, the software provides instant image analysis on each detected and captured particle during a run. For example, particle length, width, equivalent spherical diameter (ESD), area-based spherical diameter (ASD), fluorescence (if applicable), time of flight, cells per image and aspect ratio are the primary data obtained. Given the data provided by the FlowCAM the operator can develop specific algorithms for values of interest such as bio-volume, depending on the needs of the application.

4 ) The FlowCAM is a portable. Even the bench-top version used in this intercalibration study has a relatively small foot-print and can be used in the lab or at sea on board ships. The image capture system prevents problems usually associated with vibration.

5 ) The FlowCAM allows for the visualization and or detection of a wide particle size range (1 um – 1 mm). To detect across this large size range a series of objectives and flow cells would need to be used. Based on the size of the target organism to be detected in this inter-calibration study (Alexandrium), a 10x objective with a 100um depth flow cell was utilized. To examine smaller or larger particles with a sample more effectively other objectives and flow cell combinations would need to be utilized.

6 ) The FlowCAM allows for 3 different modes of detection. In this inter-calibration study, fluorescence detection mode was used. Fluorescence based detection allows for the detection and capture of fluorescent particles (containing either red or orange fluorescence – indicative of chlorophyll and phycoerithrin). Depending on the application other detection modes either scatter detection or Auto- detection mode may be used.

Disadvantages/Drawbacks

1 ) In terms of cell identification it is very important to have the best focus possible, otherwise the images will be blurry and will be difficult to analyze.

2 ) Depending on the ecosystem that is being analyzed the phytoplankton cell size range may vary greatly. Each objective and flow cell size that can be used has a minimum and maximum cell size range that’s possible (similar to the limitations of microscopy). Therefore, to best identify all phytoplankton within a given ecosystem, from 5 um particles to cells that are 100 um in size may require two FlowCAM runs – one at 4x magnification using a 300 um depth flow cell and a 10x magnification using a 100 um depth flow cell. It all depends on what magnification is acceptable for cell identification. Therefore, method development at the beginning of a particular project is important. However, if cell identification is not necessary but particle/cell size is – only one FlowCAM run may be necessary.

wghabd06.pdf (699.7Kb)

ICES O

C

ICES CM 2006/OCC:04 Ref. ACME

R EPORT OF THE

ICES-IOC W ORKING G ROUP ON H ARMFUL A LGAL B LOOM D YNAMICS

(WGHABD)

3-6 A PRIL 2006

G DYNIA , P OLAND

Contents

Executive Summary

1 Welcome and opening of the Meeting

2 Terms of Reference

3 Summary and Conclusions

4 Term of Reference a)

5 Term of Reference b)

6 Term of Reference c)

7 Term of Reference d)

8 Term of Reference e)

9 Term of Reference f)

ICES-IOC W ^ORKING G ^{ROUP ON} H ARMFUL A LGAL B LOOM D YNAMICS